Due an upgrade this weekend my Three mobile.
Any suggestion what phone to go for.?

I'm looking for something with wifi for starters. Don't want to pay more than £20 - £25.

my mate is paying £19pcm for an HTC desire on Three with a few hundred minutes, unlimited text and some data.

I would say the htc desire too if you can get it for around £20 - £25.

Another recommendation for HTC here.

Desire is good, Desire HD is great. Also look at the Galaxy S from Samsung.

I'm recommending Android handsets here because that's my preference, but try playing with them in store (and other types) to see which suit you

Don't you find the Desire a bit large? I was definitely going to go for one when my contract is up for renewal in February but I had a look in the Vodafone shop and they're huge! I have a Nokia 5800 at the moment.

No. The Desire's not a bad size at all. The Desire HD however is larger and may be too large for some, however it's perfect for me. Still fits in jeans pockets and I quite like it's size.